Apparatus for folding paper webs in rotary machines



Mayz, 1 R. MOSER 2,982,543

APPARATUS FOR FOLDING PAPER WEBS IN ROTARY MACHINES Filed Dec. 30, 19572 Sheets-Sheet l INVENTOR. jfua o/f 772 oser May 2, 196] APPARATUS FORFOLDING PAPER WEBS IN ROTARY MACHINES Filed Dec. 30, 1957 2 Sheets-Sheet2 INVENTOR RUDOLF MOSER R. MOSER 2,982,543

APPARATUS FOR FOLDING PAPER WEBS IN ROTARY MACHINES Rudolf Moser,Zofingen, Switzerland, assignor :to

Ringi'er & Co. A.G., Zofingen Aargau, Switzerland Filed Dec. 30, 1957,Ser. No. 705,972

Claims priority, application Switzerland Jan. 12,1957

2 Claims. (Cl. 270-60) This invention relates to a method and apparatusfor folding paper webs in rotary machines.

In the rotary folding apparatuseshitherto known the cutting of the paperweb to the intended length takes place before it is led to thecollecting cylinder. The grooved and knife rollers are always arrangedin such a way that the paper web is first carried from the funnel orfrom the reversing bars by means of draw members to a cutting deviceindependent of the collecting cyl-' inder, whereby, only after the cuthas taken place, the sheets are transferred to the collecting cylinderby means of tapes or transfer cylinders. Thereby the distance from thegrooved roller to the collecting cylinder must necessarily be greaterthan the intended cutting length.

Accurate folding depends chiefly on the cut sheet lengths being led tothe collecting cylinder at exactly equal distances apart. Actualpractice, however, has shown that the sheet delivery guides, eithertapes or transfer cylinders combined with tapes, are continuouslysubject to fluctuations in spite of accurate setting. Because of thestressing of the tapes, these must always be regulated. In addition, theconveying accuracy is adversely affected by the fluctuating speed of thetapes. These sources of errors render it impossible to maintain uniformfeeding of the sheet lengths onto the folding cylinder, and henceaccurate folding.

The chief object of the present invention is to eliminate the longsheet-conveying path, in order thus to accurately feed the cut materialonto the collecting cylinder.

Another object of the invention is to provide a mechanism of the typedescribed wherein a sheet is cut from the web only after its leadingportion is guided upon the collecting cylinder.

Yet another object is to provide an apparatus wherein the web is grippedto the surface of the collecting cylinder and its leading edgereleasably secured thereto after being at least partially wound aboutthe cylinder.

Further features of the invention will appear from the followingdescription and claims, taken in conjunction with the accompanyingdrawings which show by way of example a preferred form of embodiment ofthe apparatus.

In said drawing wherein like reference characters represent like orsimilar features:

Fig. 1 shows the general layout of a rotary folding apparatus withgrippers for variable paper sizes, for lengthwise fold and transversefold, i.e. funnel and cyl- I inder folds.

I Figure 2 is a sectional view to an enlarged scale, of the part of theapparatus by which the cut end of the web is transferred to and grippedby, the collecting cylinder. 7 n K In the embodiment shown, the web 11isadvanced from the rotary printing machine, not shown, over funnel 1which acts to fold the web lengthwise. The folded web next passesbetween guide rollers 2 and is drawn ice ,Patented May 2, 1961 andguided by pairs of rollers 3, the final pair of which are closelyadjacent to, and act to guide the web about, a grooved roller 4. Acut-ofi roller 5 has a knife 5a extending from its periphery along anelement of the roller and rotates in synchronism with roller 4 so thatsheets of the desired length. 7 I

As the cut end of the web continues about groove roller 4 it ,passesinto contact with the surface of collecting cylinder 6 and is almost atonce secured thereto by a belt or a series of belts 14. These belts areguided over and axially spaced along, guide rollers 6a, 7 and 8 all ofwhich are journaled with their peripheries contiguous to cylinder 6 sothat a pass of the belts contacts a corresponding portion of theperiphery of the collecting cylinder and acts positively to grip theadvancing web to the cylinder. The dimensions and relations are suchthat the cut end of the web'enters between the cylinder 6 and the belts14 before it is severed into a sheet by the next rotation of knife 5a.

Roller 8 has fingers 9, Figure 2, each of which is located between acontiguous pair of belts 14. This roller rotates synchronously withcollecting cylinder 6 in a manner such that for each rotation, itsfingers 9 coincide with an edge 13 of a gripper element'fixed in theperiphery of the cylinder and extending therealong in the directionparallel with its axis of rotation. These fingers act to bend theleading edge of the advancing sheet 12 over and about edge 13, inposition to be releasably'secured to the cylinder by grippers 10,movable into contact with edge 13 and which act in proper sequence withthe described operation of the fingers.

At the greatest cutting length, the distance S will be at mum cuttinglength of the paper, substantially agrees with the circumferential speedof the collecting cylinder 6. That is to say, the sheets will follow.each other practically without separation. But if the intended cut-'ting length is shorter than the maximum length, the speed of theadvancing web 11 will be lower, and the distance S will be greater bythe dilferenceof the cut-,

ting length. The sheets will then follow each'other at the distanceapart which is caused by the difference between the maximum cuttinglength andthe intended cutting length. V

The grippers 10 always openand close at the point of tangency withroller 8, so that the leading edge of one sheet and trailing edge of thepreceding sheet arejboth engaged by the same grippers 10. Whilepassing'over the distance S, that is to say after cutting the sheet fromthe web 11 until its engagement by the grippers 10,. V the sheet 12 ispressed to the collecting guide roller preventing any,

6 by the roller 7 and the belts 14, thus displacement from theproper'position.

By the apparatus of the present invention an inventive technicalprogress in delivering the cut material accurately on to the collectingcylinder has been achieved.

It should be understood, of course, that the fore going disclosurerelates to only a preferred embodiment of the invention and that it isintended to. cover all changes and modifications "ofthe example of theinvenj tion herein chosen for the purposes of thedisclosure, which donot constitute departures from the spirit and Y scope of the inventionset forth in the appended claims.

what lclaimis: r

'1. In a rotary web machine having means for advance-j I I ment of acontinuous web, a coacting grooved roller." and knife'roller for cuttingsaid web into sheet lengths,

means to feed the web to said rollers, a collecting cylinder providedwith spaced grippers, and contacting said grooved roller for maintainingsaid web therebetween, endless belt means having a concave runcontacting said collecting cylinder and positioned to hold the free endsof said cut sheet lengths against said collecting cylinder surface, abelt-roller about which said belt means is trained, said belt-rollercooperating with said collecting cylinder through said bclt means,fingers supported on and extending from the periphery of said beltroller and adapted to engage said sheets and push a portion thereof intosaid grippers, said collecting cylinder, said rollers and said beltmeans being driven at the same peripheral speed.

i 2. App aratus according to claim 1, wherein an additional rollercooperates through said belt with the collecting cylinder during theopening and closing of the grippers.

References Cited in the tile of this patent UNITED STATES PATENTS

